A plastic resin is easily processed, has excellent properties such as tensile strength, elastic modulus, thermal resistance, and impact resistance, and is used in various applications such as automobile parts, helmets, parts of an electric appliance, parts of a spinning machine, toys, or pipes.
Particularly, resins used for home appliances, automobile parts, and toys are in direct contact with a human body, and thus should be environmentally friendly and have excellent surface hardness. However, generally, when a resin is exposed to an external environment for a predetermined time or more, the resin is degraded by oxygen, ozone, or light in the air, and thus is easily discolored. Accordingly, to improve poor weather resistance and low strength of the resin, an additional painting or plating process is generally applied to the resin. However, such a painting or plating process may reduce efficiency and economic feasibility of a process of preparing a plastic resin, and generate a large amount of harmful materials during the painting or plating process or disposal of a product.
Therefore, various methods for enhancing characteristics of the resin such as scratch resistance, thermal resistance, and weather resistance without the painting or plating process. For example, a method of adding inorganic particles into the resin to enhance physical properties such as wear resistance and hardness was suggested. However, processibility of the plastic resin may be reduced by such a method, and impact strength and glossiness may be degraded by the addition of the inorganic particles.